16806065085781 has 2 divisors, whose sum is σ = 16806065085782. Its totient is φ = 16806065085780.

The previous prime is 16806065085749. The next prime is 16806065085809. The reversal of 16806065085781 is 18758056060861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13683829095556 + 3122235990225 = 3699166^2 + 1766985^2 .

It is a cyclic number.

It is not a de Polignac number, because 16806065085781 - 2⁵ = 16806065085749 is a prime.

It is a super-2 number, since 2×16806065085781² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16806065085181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8403032542890 + 8403032542891.

It is an arithmetic number, because the mean of its divisors is an integer number (8403032542891).

Almost surely, 2^{16806065085781} is an apocalyptic number.

It is an amenable number.

16806065085781 is a deficient number, since it is larger than the sum of its proper divisors (1).

16806065085781 is an equidigital number, since it uses as much as digits as its factorization.

16806065085781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19353600, while the sum is 61.

The spelling of 16806065085781 in words is "sixteen trillion, eight hundred six billion, sixty-five million, eighty-five thousand, seven hundred eighty-one".